I'm gonna call BS on those gradients. My car couldn't make it up a 45% grade, much less myself on a bike. I am betting the roads are probably 10-15% at most, with the paths probably not breaking more than 5%.

Some of the most burly roads around here are ~30% and people generally have to tack back and forth to make it up them. Some of the major well-known climbs are in the 15-20% sustained grades range, and people who do them talk about how brutal they are.

You are WAY off in your estimates.